Eukaryotic translation initiation: there are (at least) two sides to every story

The eukaryotic cap and poly(A) tail binding proteins, elF4E and Pab1p play important roles in the initiation of protein synthesis. The recent structures of the complex of elF4E bound to the methylated guanosine (cap) found at the 5'end of messenger RNA (mRNA). the complex of elF4E bound to peptide fragments of two related translation factors (elF4G and 4E-BP1). and the complex of the N-terminal fragment of Pab1p bound to polyadenylate RNA have revealed that elF4E and Pab1p contain at least two distinct functional surfaces. One surface is used for binding mRNA, and the other for binding proteins involved in translation initiation.